Shape memory polymers: Structure, mechanism, functionality, and applications

In the last three decades, many researches have been conducted in the field of shape memory polymers, and in the past few years, the interest in research in this field has received a lot of attention. In this study, a comprehensive and complete review of the structure, mechanism, model and applications of this category of polymers has been done. In general, the mechanisms of shape memory polymers are divided into three groups: direct thermal induction, indirect thermal induction, and optical induction, and each has its own switch unit that controls the shape structure. These switches have amorphous and semi-crystalline phase, which are defined in two phase and molecular levels. Also, increasing the mechanical properties, including the strength and toughness of shape memory polymers, is of great importance, which can increase their efficiency. Shape memory polymers can be used in medical, aerospace, textile and other industries. In the textile industry, the electrospinning process is used as a simple and efficient method for the preparation of shape memory polymer fibers and the development of their structure, and the mechanism and method of preparation of these fibers will be investigated. In the last three decades, many researches have been conducted in the field of shape memory polymers, and in the past few years, the interest in research in this field has received a lot of attention. In this study, a comprehensive and complete review of the structure, mechanism, model and applications of this category of polymers has been done.